Knife sharpener



Aug. 29, 195o J. GALLO 2,520,279

KNIFE SHARPENER Filed May 16, 1946 Patented Aug. 29, 1950 UNITEDY STATESPATENT OFFICE KNIFE SHARIENER J ohn Gallo, Medford, Mass. ApplicationMay 16, 1946, Serial N0. 670,099

1 Claim. 1

This invention relates to knife Sharpeners of the type which employpartly overlapping steel disks between which the knife is drawn.

One object of the present invention is to provide a Sharpener of thistype wherein knives having their edges beveled on one side only may besharpened, the metal being removed from the knife only on the beveledside.

A further object of the invention is to provide a Sharpener in the useof which the metal of the knife is removed at one time from one faceonly, the other face being supported and rolled adjacent to the edge.

Still another object is to reduce the cost of manufacture of Sharpenersof this type by requiring grinding of only one of the steel disks, thisgrinding being a costly operation.

Another object, where the disks are positioned on the same side of thesupport, is to provide means for limiting the lateral motion of theintermediate disk which will not require additional accuracy in the diskmountings.

For a complete understanding of this invention, reference may be had tothe accompanying drawings in which Figures l, 2 and 3 are rear, end, andfront elevations, respectively, of a Sharpener embodying the invention.

Figure 4 is a sectional view to a larger scale n line 4 4 of Figure 1.

Figures 5 and 6 are diagrammatic views illustrating the sharpeningactions of the Several disks.

Figure '7 is a view somewhat similar to Figure 4, but showing amodification.

Referring iirst to Figures 1, 2 and 3 the sharpener comprises an angularplate support l having flanges 2 and 3 arranged at an obtuse angle toeach other. The flange 2 is shown as provided with a pair of spacedperforations l for receiving fasteners (not shown) by which thesharpener may be mounted on any suitable support such as a handle memberor a table tcp, or the like. The flange 3 carries three disks 6, 1 and8. Each of these disks is shown as journaled on a rivet 9 and outwardlyof each of the disks and between it and the adjacent end of the rivet ispositioned a retaining washer I0. The central disk 1 is hardened andground around its periphery at Il to form with its side faces the sharpedges I2, and this center disk 'l is shown as positioned on the outsideface of the iiange 3. The side disks 6 and 8 are shown as arranged onthe inner face of the ange 3. These side disks are not ground to pre-Sent cutting edges, but instead may be circular punchings, which, asthey come from the stock, are formed with a rounded edge, as at I 5.These rounded edges are presented to face the center disk 1. While thesedisks are not ground, they are preferably hardened so that the hardrounded edges I5 act to roll against the edge portion of a knife bladeWhich is being drawn between the disks 6 and 1 or l' and 8 where theyoverlap and remove or turn rough edge portions or burrs to- Ward theopposite face of the knife for removal by the central disk, Such apunching is somewhat rough on its periphery, but this is notdetrimental, it being important, however, for best results that thesedisks be hardened.

The eiect of this arrangement is illustrated in Figures 5 and 6.Referring to Figure 5, the rounded disk 6 rolls against the knife edgeon one side while the center disk 1 cuts the metal away on the otherside. As shown, the sharpening is all done on the right hand edge of theknife blade as viewed in the direction of Figure 5, the knife beingdrawn forwardly between the disks 1 and 6. When the knife is drawnbetween the disks l and 8, however, the cutting is done by the grounddisk 'l on the left hand face of the knife blade, While the disk 8serves to roll the edge portion on the opposite face of the blade. Fromthis it will be seen that if a knife having a bevel on one face only,as, for example, on the right hand face as viewed in Figure 5, the knifewill be drawn between the disks 6 and 1, while if the bevel of the edgeis on the left, the knife will be drawn between the disks 1 and 8, asshown in Figure 6.

Where it is desired to sharpen the knife by removing stock from bothsides, the knife is drawn rst between the center disk 1 and one of theside disks and then between the center disk and the other side disk.

This arrangement makes possible the proper sharpening of knife bladesbeveled on one face only, although it permits sharpening of knife bladesbeveled on both faces Where this is desired. Also, since it is necessaryto grind only one of the three disks, this being the center disk l, andthis operation is relatively expensive, the cost of the Sharpener isreduced from that of constructions where all of the disks are ground aswell as hardened.

While as shown the center and side disks are positioned on oppositefaces of the flange 3, it being found desirable to separate the disksaxially, nevertheless the same principle of operation may be performedwhere all the disks are carried on the same side of the support as shownin Figure 7. Where the disks are so arranged, the

center disk 1a may be positioned between the washers l0 which are ofless diameter than and are journaled substantially coaxially with theside disks on the side disk rivets, as shown. All the disks are looselyjournaled on the rivets and the rivets are loosely7 set in the support,this looseness requiring no great accuracy in making or assembling theparts so that quantity production is easy and cheap, and it permitsself-adjustment and rotation of the` disks to present various portionsfroin Ytime to time into operative relation to the knife blade thus todistribute the wear. Since the central disk is spaced from the sup.`port with this construction, it might have undue play were it not forthe washers I0 against one or the other of which it may be pressed bypressure exerted by the knife blade 5inserted between the center diskand the opposite side disk. These Washers I0 then serve as stops withone 2or the other of which the central disk may engage and Since .this@Dieci iS with the @des 0f the @enter disk; it" hes il? .detrimental@Heet .9.11 .its slitting ds@ These washers .I9 .may be .fermes .esPphiess .Or @ents .Similar t9' the A.Sigle disks ses? .83'lbisf-rrar1semsni Qf ,disks .and .Washers may be used, if desiree.,.Where @.11 @i the .disks ai@ tiene@ wie .thus beve uliinsesigesif?Qivfraiiee ille. knife preferably .drawn frein .the had; feel@ @.f the@ange ..3 toward .the forward face, and a direction substantiallyparallel to the base ange 2. Thisprovides a shearing out onthe knifeblade by the center disk'l. i

From the foregoing description of an embodiment of this invention, itshould be evident to those skilled in the art that various changes andmodifications might be made Without departing from its spirit or scope.

I claim:

A device of the class described, comprising a support, a, center diskand two side disks loosely journaled to said support in partlyoverlapping relation on either side of said center disk, said. centerdisk being hardened and having a ground periphery presenting cuttingedges with its side faces, and vWashers journaled Acoaxial with saidside disks in the plane of said central disk and `forming stops with oneor the other of which said central disk may engage to limit the lateralmotion of said central disk by pressure of a kniie blade insertedbetween said central disk and the Qpposite side disk.

JOHN GALLO.

REFERENCES CITED The following 4references Yare of record in `the @le @fthis Patenti UNITED STATES PATENTS Number Name Date 591,028 Bauroth r..-Oct. 5, 1397 l,`58g,3i1,2 Wright p May 1l, 1925 1,594,198 Holtzman July27, 1926 21,4%63909 .Davis -n.- Aug. l0, 1948 FOREIGN PATENTS NumberCountry Date 97,110 ySwitzerland ec. l, 1922 113,591 Switzerland June1G, 1925

